I have had several people ask why walking and not driving, biking, flying, etc ...
There are several reasons.
First, I need time. I need time to process some pretty heavy stuff that has weighed on me for quite some time. A very long walk by myself will give me hours each day to think before I arrive at my next destination.
Second, I don't have the money for a trip via car or plane. All of those options cost more than I can afford.
Third, I am less likely to pass by interesting places because I didn't see them if I am walking. With a car, I might drive past something and not see it because I am focused on driving. I want to find unique places, and take photos and videos of nature and manmade curiosities along the way.
Last, I enjoy walking. I really enjoy it. I can put on music or an audiobook and walk for 6 or 7 hours without realizing how much time has passed. Sure, my feet get tired and sore, and I get kind of worn out, but those are both ok things. Being a bit sore, tired, or hungry are not deal breakers. My body is strong. Not necessarily as functional as I'd like, but it's tough.
So I'm walking, and I don't yet know how far or how long. Hopefully for a long time. There's a lot out there I want to see.